Vertical shaft impact (VSI) crushers find widespread use for crushing a variety of hard materials, such as rock, ore, demolished constructional materials and the like. Typically, a VSI crusher comprises a housing that accommodates a horizontally aligned rotor mounted at a generally vertically extending main shaft. The rotor is provided with a top aperture through which material to be crushed is fed under gravity from an elevated position. The centrifugal forces of the spinning rotor eject the material against a wall of compacted feed material or specifically a plurality of anvils or retained material such that on impact with the anvils and/or the retained material the feed material is crushed to a desired size.
The rotor commonly comprises a horizontal upper disc and a horizontal lower disc. The upper and lower discs are connected and separated axially by a plurality of upstanding rotor wall sections. The top aperture is formed within the upper disc such that the material flows downwardly towards the lower disc between the wall sections and is then ejected at high speed towards the anvils. A replaceable distributor plate is mounted centrally on the lower disc and acts to protect it from the material feed. Example VSI crusher distributor plates are described in WO 95/10359; WO 01/30501; US 2006/0011762; US 2008/0135659 and US 2011/0024539.
As will be appreciated, due to the abrasive nature of the crushable material, the distributor plate and the surrounding wear plates (that sit radially outside distributor plate and are mounted to both the upper and lower rotor discs) are subject to substantial abrasive wear which significantly reduces their operational lifetime and increases the frequency of servicing intervals. Accordingly, it is a general objective to maximise the operational lifetime of the plates. US 2003/0213861; US 2004/0251358; WO 2008/087247; WO 2004/020101 and WO 2015/074831 describe wear plates having embedded tungsten carbide inserts exposed at the wear or contact face of the plate. However, conventional plates due to the choice of material of the component parts tend to be thick and heavy which introduces a number of a significant disadvantages. In particular, conventional plates are typically difficult to handle and in particular manoeuvre to and from the rotor. Additionally, the thickness of conventional plates reduces the free-volume within the rotor though which material is capable of flowing that, in turn, restricts crushing capacity and increases the likelihood of rotor chocking. Accordingly, what is required is a wear plate mountable at a VSI crusher rotor that addresses the above problems.